CN115155217A

CN115155217A - Oil mist filter

Info

Publication number: CN115155217A
Application number: CN202210919172.3A
Authority: CN
Inventors: 孙敏; 凌林; 丁键
Original assignee: Suzhou Hante Environmental Protection Equipment Co ltd
Current assignee: Suzhou Hante Environmental Protection Equipment Co ltd
Priority date: 2022-08-02
Filing date: 2022-08-02
Publication date: 2022-10-11

Abstract

The application relates to the field of air purification, in particular to an oil mist filter, which comprises a box body, wherein an air box, an air pipe and an air outlet are arranged on the box body; a first filtering mechanism, a second filtering mechanism and a third filtering mechanism are arranged in the box body, the first filtering mechanism is used for separating dust in air, the second filtering mechanism and the third filtering mechanism are both used for separating oil mist, and the particle size of oil drops separated by the third filtering mechanism is smaller than that of oil drops separated by the second filtering mechanism; the air pipe is communicated with the first filtering mechanism, the second filtering mechanism is respectively communicated with the first filtering mechanism and the third filtering mechanism, and the air box is respectively communicated with the third filtering mechanism and the air outlet; the second filtering mechanism comprises at least two filtering nets which are sequentially arranged along the air flowing direction, and the median particle diameters of the filtering nets are sequentially reduced along the air flowing direction; the box body is provided with a cleaning component for cleaning the filter screen. This application has the effect of extension high efficiency air cleaner duty cycle.

Description

Oil mist filter

Technical Field

The application relates to the field of air purification, in particular to an oil mist filter.

Background

In the machining industry, in order to effectively reduce the temperature of a workpiece during machining, cooling liquid is often used to cool the workpiece. When the cooling liquid cools the hot workpiece, a large amount of oil mist is generated to be dispersed and float in the air, so that the production environment of a factory and the body health of workers are influenced.

Because the particle size of oil mist liquid drop is not of uniform size, the machining enterprise often uses high-efficient air cleaner to purify the air for avoiding the oil mist to the influence of production environment.

When the high-efficiency air filter works, the high-efficiency air filter is easy to block along with the accumulation of dust and oil drops on a filter element of the filter, so that the working period of the high-efficiency air filter is short, the filter element needs to be frequently maintained and replaced, and the use cost is high.

To this end, the present application provides an oil mist filter to solve the above problems.

Disclosure of Invention

In order to prolong the work cycle of the high-efficiency air filter, the application provides an oil mist filter.

The application provides an oil mist filter adopts following scheme:

an oil mist filter, characterized in that: the air box comprises a box body, wherein an air box, an air pipe and an air outlet are arranged on the box body; a first filtering mechanism, a second filtering mechanism and a third filtering mechanism are arranged in the box body, the first filtering mechanism is used for separating dust in air, the second filtering mechanism and the third filtering mechanism are both used for separating oil mist, and the particle size of oil drops separated by the third filtering mechanism is smaller than that of oil drops separated by the second filtering mechanism;

the air pipe is communicated with the first filtering mechanism, the second filtering mechanism is respectively communicated with the first filtering mechanism and the third filtering mechanism, and the air box is respectively communicated with the third filtering mechanism and the air outlet;

the second filtering mechanism comprises at least two filtering nets, the filtering nets are sequentially arranged along the air flowing direction, and the median diameters of the filtering nets are sequentially reduced along the air flowing direction; the box body is provided with a cleaning assembly for cleaning the filter screen, and the cleaning assembly is communicated with a water pipe.

By adopting the technical scheme, the filter screen in the second filter mechanism can filter oil mist liquid drops with larger particle sizes, and the gathering of oil mist on the third filter mechanism can be reduced, so that the working period of the air filter can be prolonged.

The filter screens with different median diameters can filter oil mist liquid drops with different particle diameters, and the filter screens with different median diameters are matched with each other, so that the condition that a large amount of oil mist is gathered on the same filter screen to cause blockage can be avoided as much as possible, and the working period of the air filter is prolonged.

The cleaning component can clean the oil mist gathered on the filter screen, thereby prolonging the service life of the filter screen and being beneficial to prolonging the working period of the air filter.

The first filtering mechanism separates out dust, and can reduce the accumulation of the dust on the second filtering mechanism and the third filtering mechanism, thereby being beneficial to prolonging the working period of the air filter.

In a specific embodiment, a first filter chamber, a second filter chamber, an air duct and a third filter chamber are arranged in the box body, and the first filter chamber, the second filter chamber, the air duct and the third filter chamber are arranged in sequence;

the first filtering mechanism is arranged in the first filtering chamber, and the air pipe penetrates through the box body and is communicated with the first filtering mechanism; the second filtering mechanism is arranged in the second filtering chamber; the third filtering mechanism and the air box are arranged in a third filtering chamber, and the air outlet is positioned at the top of the third filtering chamber;

the box body is also provided with a first ventilation opening, a second ventilation opening and a third ventilation opening, the first filter chamber and the second filter chamber are communicated through the first ventilation opening, the second filter chamber is communicated with the air duct through the second ventilation opening, and the air duct is communicated with the third filter chamber through the third ventilation opening;

the air containing oil mist is discharged from the air outlet after passing through the air pipe, the first filtering mechanism, the first ventilation opening, the second filtering mechanism, the second ventilation opening, the air duct, the third ventilation opening, the third filtering mechanism and the air box in sequence.

In a specific possible embodiment, the first filtering mechanism comprises an air cylinder and a spraying assembly positioned in the air cylinder, the spraying assembly is communicated with a water pipe, and the spraying assembly is used for spraying water to the air in the air cylinder; a first partition plate is arranged in the first filter chamber, and the air duct and the spraying assembly are arranged on the first partition plate; one end of the air duct is communicated with the air pipe, and the other end of the air duct is communicated with the first ventilation opening after penetrating through the first partition plate.

Through adopting above-mentioned technical scheme, the spray assembly gives the air water spray in the dryer, and the dust in the air triggers the agglomeration to subside after being moistened to the condition that the dust got into the second filter chamber has been reduced.

In a specific possible embodiment, the second filtering mechanism includes a collecting plate disposed in the second filtering chamber, the collecting plate and the filtering net being disposed in order in the air flowing direction; the gathering plate is provided with gathering holes penetrating through the gathering plate, and the diameter of one end, close to the filter screen, of each gathering hole is smaller than that of the other end, far away from the filter screen, of each gathering hole.

Through adopting above-mentioned technical scheme, under the effect of gathering the hole, gather the hole air current velocity of moving and accelerate for the oil mist in the air bumps and fuses, thereby the particle size increase of oil mist liquid droplet is changeed by the filter screen filtration, and then has reduced the volume that gets into the oil mist in the third filter chamber, is favorable to prolonging air cleaner's duty cycle.

In a specific possible embodiment, the second filtering mechanism comprises a baffling separation assembly arranged in the second filtering chamber, the baffling separation assembly is used for separating oil mist in air, and the baffling separation assembly and the filtering screen are arranged in sequence along the air flow direction; the baffling separation assembly comprises an installation rod and a plurality of baffling plates, the plurality of baffling plates are distributed in a staggered mode in the vertical direction, the installation rod is connected to the inner wall of the second filtering chamber, and the plurality of baffling plates are connected to the inside of the second filtering chamber through the installation rod.

By adopting the technical scheme, when the air containing the oil mist flows through the baffle plate, oil mist droplets can collide with the baffle plate due to inertia and are attached to the baffle plate, so that the separation of the oil mist in the air is facilitated; with the gathering of oil mist drops on the baffle plate, the oil mist is gathered into oil drops, and finally the oil drops drop from the baffle plate.

In a specific embodiment, the second filter mechanism further comprises a mounting bracket connected to the inner wall of the second filter chamber, and the filter screen is detachably connected to the bracket mounting; and a guide plate is arranged on the mounting bracket.

In a specific embodiment, the third filter means comprises a filter element which intercepts oil mist of a smaller particle size than the second filter means.

In a specific embodiment, the tank is provided with a backflow collecting assembly, and the backflow collecting assembly is respectively communicated with the second filtering chamber and the third filtering chamber.

Through adopting above-mentioned technical scheme, the waste liquid in second filter chamber and the third filter chamber can be collected to the backward flow collection subassembly.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the oil mist liquid drops of different particle diameters can be filtered to the filter screen of different median diameters, and the filter screen of a plurality of different median diameters is mutually supported, can avoid a large amount of oil mist to gather on same filter screen and lead to the condition of jam as far as possible, washs the oil mist that the subassembly can wash on the filter screen and gather simultaneously to can prolong the length of service of filter screen, be favorable to prolonging air cleaner's duty cycle.

2. Under the effect of gathering the hole, the oil mist in the air bumps and fuses to the particle size increase of oil mist liquid droplet is changeed by the filter screen and is filtered, and then has reduced the volume of entering third filter chamber oil mist, is favorable to prolonging air cleaner's duty cycle.

Drawings

FIG. 1 is a schematic perspective view of an oil mist filter in example 1 of the present application.

FIG. 2 is a schematic perspective view of the inside of an oil mist filter in example 1 of the present application.

Fig. 3 is a schematic perspective view of the inside of the first filter chamber in embodiment 1 of the present application.

Fig. 4 is an internal perspective view of the spray assembly in embodiment 1 of the present application.

Fig. 5 is a schematic perspective view of the inside of the second filter chamber in embodiment 1 of the present application.

Fig. 6 is a perspective view of a baffle separating unit in embodiment 1 of the present application.

Fig. 7 is a schematic perspective view of the inside of the third filter chamber in embodiment 1 of the present application.

Fig. 8 is a schematic internal perspective view of a backflow collection assembly in embodiment 1 of the present application.

Fig. 9 is an enlarged schematic view of a portion a of fig. 7.

Fig. 10 is a perspective view of the inside of the second filtering chamber in embodiment 2 of the present application.

Fig. 11 is a schematic perspective view of the inside of the second filter chamber in embodiment 3 of the present application.

Fig. 12 is a schematic sectional view of a collecting plate in embodiment 3 of this application.

Description of reference numerals:

1. a box body; 11. a first filter chamber; 111. an upper space; 112. a lower space; 12. a second filtering chamber; 13. an air duct; 14. a third filtration chamber; 15. a first air vent; 16. a second ventilation opening; 17. a third vent; 18. an air duct; 19. an air box; 20. an air outlet; 21. an air duct; 22. a sprinkler head; 23. a water spray pipe; 24. a first partition plate; 25. a floating oil level meter; 26. a water pump; 27. a water inlet pipe; 31. a first filter screen; 32. a second filter screen; 33. a third filter screen; 34. a first mounting bracket; 35. a second mounting bracket; 36. a third mounting bracket; 37. a nozzle; 38. a baffle plate; 39. mounting a rod; 40. a first baffle; 41. a first fluid conduit; 42. a second baffle; 43. a second liquid flow pipe; 44. a third baffle; 45. a third partition plate; 46. a collecting plate; 47. an aggregation hole; 51. a HEPA filter; 52. a filter mounting bracket; 53. a second partition plate; 54. a third effluent pipe; 61. a reflux pump; 62. a first electrically powered ball valve; 63. a second electrically operated ball valve; 64. a first return pipe; 65. a filter housing; 66. and a tuning fork liquid level meter.

Detailed Description

The present application is described in further detail below with reference to figures 1-12.

The application provides an oil mist filter.

Example 1

Referring to fig. 1 and 2, an oil mist filter comprises a box body 1, wherein a first filter chamber 11, a second filter chamber 12, an air duct 13 and a third filter chamber 14 are sequentially arranged in the box body 1; the box body 1 is also provided with a first ventilation opening 15 positioned at the lower end of the first filtering chamber 11, a second ventilation opening 16 positioned at the upper end of the second filtering chamber 12 and a third ventilation opening 17 positioned at the upper end of the air duct 13, the first ventilation opening 15 is positioned on the side wall of the first filtering chamber 11 and is communicated with the second filtering chamber 12, the second ventilation opening 16 is positioned on the side wall of the second filtering chamber and is communicated with the air duct 13, and the third ventilation opening 17 is positioned on the side wall of the air duct 13 and is communicated with the third filtering chamber 14.

Referring to fig. 3 and 4, a first partition plate 24 is arranged in the first filtering chamber 11 and located above the first ventilation opening 15, four sides of the first partition plate 24 are connected with the side wall of the first filtering chamber 11, and the first partition plate 24 divides the first filtering chamber 11 into an upper space 111 and a lower space 112; the side wall of the upper space 111 is connected with an air pipe 18, and the air pipe 18 penetrates through the side wall of the upper space 111 and then extends out of the box body 1; a first filtering mechanism positioned in the upper space 111 is arranged on the first separating plate 24, the first filtering mechanism comprises an air duct 21 and a spraying assembly, and the air duct 21 and the spraying assembly are both connected to the first separating plate 24; one end of the air duct 21 is communicated with the air duct 18, and the other end of the air duct passes through the first partition plate 24 and then is communicated with the lower space 112; the spray assembly comprises a water spraying pipeline 23 and two water spraying heads 22 which are all located in the air duct 21, the two water spraying heads 22 are all located in the air duct 21, the water spraying pipeline 23 is connected onto the first partition plate 24, the two water spraying heads 22 are all connected onto the water spraying pipeline 23, and the two water spraying heads 22 are all communicated with the water spraying pipeline 23.

A water pump 26, a floating oil level meter 25 and a water inlet pipe 27 are arranged on the first partition plate 24, the water pump 26 is communicated with the water spraying pipeline 23, and a water inlet joint of the water pump 26 penetrates through the first partition plate 24 and then extends into the lower space 112; the floating oil level meter 25 penetrates through the first partition plate 24 and then extends into the lower space 112, and the floating oil level meter 25 is used for measuring the water level in the lower space 112; one end of the water inlet pipe 27 penetrates the first partition plate 24, and the other end penetrates the sidewall of the upper space 111 and then is communicated with the water pipe.

Therefore, water can be injected into the lower space 112 through the water inlet pipe 27, the water in the lower space 112 can be sent into the water injection pipe 23 by the water pump 26 and injected into the air duct 21 from the water injection head 22, and dust contained in the air duct 21 can be agglomerated and settled in the lower space 112 after being wetted, so that the dust contained in the air can be removed.

Referring to fig. 5 and 6, a second filtering mechanism is arranged in the second filtering chamber 12, and the second filtering mechanism is positioned between the first ventilation opening 15 and the second ventilation opening 16; the second filtering mechanism comprises a baffling separation component, the separation component comprises four mounting rods 39 and a plurality of baffle plates 38, the four mounting rods 39 are parallel to each other, and each baffle plate 38 is parallel to any one mounting rod 39; four mounting rods 39 are connected to the inner wall of the second filtering chamber 12, each baffle plate 38 is connected with two mounting rods 39, and a plurality of baffle plates 38 are distributed in a staggered manner in the vertical direction; when the air containing oil mist flows through the baffle plate 38, oil mist droplets are attached to the baffle plate 38 due to the collision of the oil mist droplets with the baffle plate 38 by inertia, thereby facilitating the separation of the oil mist in the air; as the mist droplets accumulate on the baffle 38, the mist collects into droplets, which eventually drip off the baffle 38.

The second filtering mechanism further comprises a first filter screen 31, a second filter screen 32 and a third filter screen 33 which are sequentially arranged along the vertical direction, wherein the first filter screen 31, the second filter screen 32 and the third filter screen 33 are inclined in the same direction, the first filter screen 31 is positioned below the second filter screen 32, the average median diameter of the first filter screen 31 is 3 micrometers, the average median diameter of the second filter screen 32 is 1 micrometer, and the average median diameter of the third filter screen 33 is 0.6 micrometer.

The second filtering mechanism also comprises a first mounting bracket 34, a second mounting bracket 35 and a third mounting bracket 36 which are connected to the inner wall of the second filtering chamber 12, and the third mounting bracket 36 is attached to four inner walls of the second filtering chamber 12; the first filter screen 31 is connected to the first mounting bracket 34 through screws, and the second filter screen 32 is connected to the second mounting bracket 35 through screws; four hanging rods are arranged on the third filter screen 33, four hooks are arranged on the third mounting bracket 36, and each hanging rod is hung on one of the hooks.

The side edge of the first mounting bracket 34 which is positioned at the lowest position among the four side edges is connected with a first guide plate 40, the other three side edges are all attached to the side wall of the second filtering chamber 12, the first guide plate 40 is attached to the corresponding side wall of the second filtering chamber 12, the first guide plate 40 is provided with a first through hole, the bottom surface of the first guide plate 40 is connected with a first fluid pipe 41, the first fluid pipe 41 is communicated with the first through hole, and the end part of the first fluid pipe 41 is bent upwards; the side that is located the below in four sides of second installing support 35 is connected with second guide plate 42, and three other sides all laminate with the lateral wall of second filter chamber 12, and second guide plate 42 laminates with the second filter chamber 12 lateral wall that corresponds, is provided with the second on the second guide plate 42 and perforates, is connected with second flow liquid pipe 43 on the second guide plate 42 bottom surface, and second flow liquid pipe 43 and the second perforates the intercommunication, and the tip kickup of second flow liquid pipe 43.

Be equipped with on the inner wall of second filter chamber 12 and wash the subassembly, wash the subassembly and include two nozzles 37, two nozzles 37 all with water pipe intercommunication, two nozzles 37 are respectively towards first filter screen 31 and second filter screen 32. First filter 31 and second filter 32 may be cleaned by spraying water through nozzles 37 toward first filter 31 and second filter 32, respectively.

Referring to fig. 7, a third filtering mechanism is arranged in the third filtering chamber 14, and the third filtering mechanism is located above the third ventilation opening 17; the third filtering mechanism comprises a HEPA filter 51 and a filter mounting frame 52, the filter mounting frame 52 is connected to the side wall of the third filtering chamber 14, the HEPA filter 51 is connected to the filter mounting frame 52, and the average median diameter of the filter core of the HEPA filter 51 is 0.3 mu m; a tuning fork level gauge 66 is provided on the side wall of the third filter chamber 14, the tuning fork level gauge 66 being located below the third filter mechanism.

A second partition plate 53 positioned above the HEPA filter 51 is arranged in the third filtering chamber 14, and four sides of the second partition plate 53 are connected with the side wall of the third filtering chamber 14; a third through hole is formed in the second partition plate 53, an air box 19 is arranged on the second partition plate 53, and an air inlet of the air box 19 is communicated with the third through hole; the top of the third filtering chamber 14 is provided with an air outlet 20.

So that air can enter the third filter chamber 14 from the third ventilation opening 17 by the air box 19, and the air is filtered by the HEPA filter 51, blown into the space of the third filter chamber 14 above the second partition plate 53, and finally blown out of the box body 1 from the ventilation opening 20.

The second partition plate 53 is provided with a third through hole, the bottom surface of the second partition plate 53 is connected with a third flow pipe 54, the third flow pipe 54 penetrates through the filter mounting frame 52 and then extends into the lower part of the filter mounting frame 52, and the end part of the third flow pipe 54 is bent upwards.

Referring to fig. 8 and 9, a backflow collecting assembly is arranged on the outer wall of the box body 1, the backflow collecting assembly comprises a backflow pump 61, a first electric ball valve 62 and a second electric ball valve 63, and the first electric ball valve 62 and the second electric ball valve 63 are communicated with the backflow pump 61 through pipelines.

The first electric ball valve 62 is communicated with the second filtering chamber 12 through a first return pipe 64, the first return pipe 64 is positioned at the lower end of the box body 1, the first return pipe 64 is connected to the side wall of the second filtering chamber 12 and penetrates through the side wall of the second filtering chamber 12, a filter cover 65 is arranged in the second filtering chamber 12, and the filter cover 65 is positioned at a water inlet of the first return pipe 64.

The second electric ball valve 63 is communicated with the third filtering chamber 14 through a second return pipe, the inlet of which is located at the lower end of the tank 1.

The implementation principle of the oil mist filter of the embodiment of the application is as follows:

under the action of the air box 19, air containing oil mist enters the air duct 21 from the air inlet pipe 18, the nozzles 37 in the air duct 21 can spray water to the air in the air duct 21, and dust in the air is wetted and then converged to fall into the lower space 112, so that the dust entering the second filtering mechanism or the third filtering mechanism can be reduced, and the working period of the air filter can be prolonged.

After the air containing oil mist is filtered by the first filter 31, the second filter 32 and the third filter 33, the accumulation of oil mist on the HEPA filter 51 can be reduced, thereby being beneficial to the extension of the working period of the HEPA filter 51. The first filter screen 31 in the second filter chamber 12 can filter oil drops with the particle size larger than 3 μm, the second filter screen 32 can filter oil drops with the particle size larger than 1 μm, the third filter screen 33 can filter oil drops with the particle size larger than 0.6 μm, oil drops with different particle sizes are respectively filtered through filter screens with different median diameters, the condition that a large amount of oil mist is gathered on the same filter screen to cause blockage can be avoided as much as possible, and therefore the working period of the air filter is favorably prolonged.

The nozzles 37 spray water to the first filter screen 31 and the second filter screen 32 respectively, so that the first filter screen 31 and the second filter screen 32 can be cleaned, the service life of the filter screens can be prolonged, and the working period of the air filter can be prolonged.

Example 2

Referring to fig. 10, the present embodiment is different from embodiment 1 in that the second filter mechanism includes two second filter screens 32 and a third filter screen 33, the two second filter screens 32 are respectively connected to a first mounting bracket 34 and a second mounting bracket 35 through screws, the first mounting bracket 34, the second mounting bracket 35 and the third bracket are sequentially arranged along a vertical direction, and the second mounting bracket 35 is located above the first mounting bracket 34.

The side that lies in the below in four sides of first installing support 34 is connected with first guide plate 40, two sides adjacent with the side that is connected with first guide plate 40 in four sides of first installing support 34 all with the lateral wall laminating of second filter chamber 12, first guide plate 40 and the lateral wall laminating of second filter chamber 12 that corresponds, leave first clearance between the side relative with the side that is connected with first guide plate 40 in four sides of first installing support 34 and the lateral wall of second filter chamber 12, be provided with first perforation on the first guide plate 40, be connected with first flow pipe 41 on the first guide plate 40 bottom surface, first flow pipe 41 and first perforation intercommunication, the tip kickup of first flow pipe 41.

The side located at the lowest of the four sides of the second mounting bracket 35 is connected with a third flow guide plate 44, the other three sides are attached to the side wall of the second filtering chamber 12, a second gap is left between the third flow guide plate 44 and the corresponding side wall of the second filtering chamber 12, and a through hole is formed in the third flow guide plate 44.

The third baffle 44 that second installing support 35 connects is connected with third division board 45, and in the four sides of third division board 45 and first installing support 34 with be connected with the opposite side of the side that is connected with first baffle 40, third division board 45 all laminates with the lateral wall of second filter chamber 12 with two adjacent sides of the side of being connected third baffle 44.

Thus, a larger area of the second filter 32 in the second filter chamber 12 is available for filtering the oil mist, thereby increasing the ventilation in the second filter chamber 12 and facilitating an improved working efficiency of the oil mist filter.

Example 3

Referring to fig. 11 and 12, the present embodiment is different from embodiment 2 in that the second filtering mechanism further includes a collecting plate 46, the collecting plate 46 is located between the separating assembly and the first mounting bracket 34, four sides of the collecting plate 46 are respectively connected to corresponding sides of the second filtering chamber 12, a plurality of collecting holes 47 are formed in the collecting plate 46, and a diameter of one end of the collecting hole 47 located on the top surface of the collecting plate 46 is smaller than a diameter of one end of the collecting hole 47 located on the bottom surface of the collecting plate 46.

Under the action of the gathering holes 47, the air flowing speed in the gathering holes 47 is accelerated, so that the oil mist in the air is collided and fused, the particle size of oil mist droplets is increased, the oil mist droplets are easily filtered by the filter screen, the amount of the oil mist entering the third filter chamber 14 is reduced, and the working period of the air filter is prolonged.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: equivalent changes in structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. An oil mist filter, characterized in that: the air-conditioning box comprises a box body (1), wherein an air box (19), an air pipe (18) and an air outlet (20) are arranged on the box body (1); a first filtering mechanism, a second filtering mechanism and a third filtering mechanism are arranged in the box body (1), the first filtering mechanism is used for separating dust in air, the second filtering mechanism and the third filtering mechanism are both used for separating oil mist, and the particle size of oil drops separated by the third filtering mechanism is smaller than that of oil drops separated by the second filtering mechanism;

the air pipe (18) is communicated with a first filtering mechanism, the second filtering mechanism is respectively communicated with the first filtering mechanism and the third filtering mechanism, and the air box (19) is respectively communicated with the third filtering mechanism and the air outlet (20);

the second filtering mechanism comprises at least two filtering nets, the filtering nets are sequentially arranged along the air flowing direction, and the median diameters of the filtering nets are sequentially reduced along the air flowing direction; the box body (1) is provided with a cleaning assembly for cleaning the filter screen, and the cleaning assembly is communicated with a water pipe.

2. An oil mist filter according to claim 1, characterized in that: a first filtering chamber (11), a second filtering chamber (12), an air duct (13) and a third filtering chamber (14) are arranged in the box body (1), and the first filtering chamber (11), the second filtering chamber (12), the air duct (13) and the third filtering chamber (14) are sequentially arranged;

the first filtering mechanism is arranged in a first filtering chamber (11), and the air pipe (18) penetrates through the box body (1) and then is communicated with the first filtering mechanism; the second filtering mechanism is arranged in a second filtering chamber (12); the third filtering mechanism and the air box (19) are arranged in a third filtering chamber (14), and the air outlet (20) is positioned at the top of the third filtering chamber (14);

the box body (1) is further provided with a first ventilation opening (15), a second ventilation opening (16) and a third ventilation opening (17), the first filtering chamber (11) is communicated with the second filtering chamber (12) through the first ventilation opening (15), the second filtering chamber (12) is communicated with the air duct (13) through the second ventilation opening (16), and the air duct (13) is communicated with the third filtering chamber (14) through the third ventilation opening (17);

the air containing oil mist is discharged from an air outlet (20) after passing through the air pipe (18), the first filtering mechanism, the first ventilation opening (15), the second filtering mechanism, the second ventilation opening (16), the air duct (13), the third ventilation opening (17), the third filtering mechanism and the air box (19) in sequence.

3. An oil mist filter according to claim 2, characterized in that: the first filtering mechanism comprises an air duct (21) and a spraying assembly positioned in the air duct (21), the spraying assembly is communicated with a water pipe, and the spraying assembly is used for spraying water to air in the air duct (21); a first partition plate (24) is arranged in the first filter chamber (11), and the air duct (21) and the spraying assembly are both arranged on the first partition plate (24); one end of the air duct (21) is communicated with the air duct (18), and the other end of the air duct penetrates through the first partition plate (24) and then is communicated with the first ventilation opening (15).

4. An oil mist filter according to claim 2, characterized in that: the second filtering mechanism comprises a gathering plate (46) arranged in a second filtering chamber (12), and the gathering plate (46) and the filtering net are arranged in sequence along the air flow direction; the gathering plate (46) is provided with gathering holes (47) penetrating through the gathering plate (46), and the diameter of one end, close to the filter screen, of the gathering holes (47) is smaller than that of one end, far away from the filter screen, of the gathering holes (47).

5. An oil mist filter according to claim 2, characterized in that: the second filtering mechanism comprises a baffling separation component arranged in a second filtering chamber (12), the baffling separation component is used for separating oil mist in air, and the baffling separation component and the filtering screen are sequentially arranged along the air flowing direction; the baffling separation assembly comprises mounting rods (39) and a plurality of baffling plates (38), the baffling plates (38) are distributed in a staggered mode in the vertical direction, the mounting rods (39) are connected to the inner wall of the second filtering chamber (12), and the baffling plates (38) are connected into the second filtering chamber (12) through the mounting rods (39).

6. An oil mist filter according to claim 2, characterized in that: the second filtering mechanism also comprises a mounting bracket connected to the inner wall of a second filtering chamber (12), and the filtering screen is detachably connected to the bracket; and a guide plate is arranged on the mounting bracket.

7. An oil mist filter according to claim 1, characterized in that: the third filtering mechanism comprises a filter element, and the particle size of the oil mist intercepted by the filter element is smaller than that of the oil mist intercepted by the second filtering mechanism.

8. An oil mist filter according to claim 1, characterized in that: and a backflow collecting assembly is arranged on the box body (1), and is respectively communicated with the second filtering chamber (12) and the third filtering chamber (14).